This study aims to coordinate the efforts of several investigators on the Cornell University Campus in their studies on membranes of normal and cancer cells. The greatest emphasis will be placed on the plasma membrane, and the following parameters will be studied: (1) the mechanism of lactic acid excretion in normal and cancer cells; (2) the mobility of phospholipids and proteins in the plasma membranes of normal and cancer cells; (3) permeability changes due to phosphorylation of transformed cells by external ATP; (4) receptor-controlled ion fluxes in normal and cancer cells; (5) characterization of the glucose transporter of the plasma membrane; (6) molecular interactions between cells and lectins and hormones; (7) structure of the plasma membrane and membrane components as studied by electron microscopy.